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alkej-449
Effect of Laser Shock Peening on the Fatigue Behavior and Mechanical Properties of Composite Materials
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In this study, Laser Shock Peening (LSP) effect on the polymeric composite materials has been investigated experimentally. Polymeric composite materials are widely used because they are easy to fabricate and have many attractive features. Unsaturated polyester resin as a matrix was selected and Aluminum powder with micro particles as a reinforcement material was used with different volume fraction (2.5%, 5% and 7.5%). Hand lay-up process was used for preparation the composites. Fatigue test with constant amplitude with stress ratio (R =-1) was carried out before and after LSP process with two levels of energy (1Joule and 2Joule). The result showed an increase in the endurance strength of 25.448% at 7.5% volume fraction when peened is 1J laser energy. Also, the ultimate strength and Young’s modulus were increased by 6.474% and 10.588% respectively after LSP with the same laser energy.  On the other hand, composites with (2.5% and 5%) volume fraction manifested a reduction in the mechanical and fatigue strength especially when treated by 2J laser energy.

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Publication Date
Wed Mar 15 2023
Journal Name
Journal Of Baghdad College Of Dentistry
Effect of a novel coating material on the microleakage of glass hybrid restoration in primary teeth – An in vitro study
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Background: Glass ionomer restorations are widely employed in the field of pediatric dentistry. There is a constant demand for a durable restoration that remains functional until exfoliation. This study aimed to measure and compare the effect of a novel coating material (EQUIA Forte Coat) on the microleakage of glass hybrid restoration (EQUIA Forte HT) in primary teeth. Material and method: Thirty cavitated (class-II) primary molars were allocated randomly into two groups based on the coat application; uncoated (control) and coated group (experimental). Cavities were prepared by the use of a ceramic bur (CeraBur) and restored with EQUIA Forte HT with or without applying a protective coat (EQUIA Forte Coat). Samples went through the therm

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Publication Date
Sun Oct 13 2013
Journal Name
Journal Of Advances In Chemistry
Effect of Aqueous Extract of Vitis Vinifera l. Leaf on the Rabbit Females Have Highly Thyroxine Induced by Levothyroxine Sodium‏
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L-Thyroxine(T4) and triiodothyronine(T3)are iodine-containing hormones produced from thyroglobulin in the thyroid follicular cells. The stimulation of metabolic rate and regulation of growth and development by these hormones appear to be due to their effects on DNA transcription and, thus, protein synthesis. The aqueous extract of vitis vinifera L. was investigated for its effect on hormones in rabbits. The aqueous extract of plant at a dose level of 50µg/rabbit showed highly significant (p<0.05)on levels of hormones T4, TSH but TSH no significant. L-thyroxine sodium treated group showed a highlysignificant increase in T3 and T4 while there was a highly significant decrease in TSH. From the above results, it is concluded for the first time

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Publication Date
Wed Mar 15 2023
Journal Name
Journal Of Baghdad College Of Dentistry
Effect of a novel coating material on the microleakage of glass hybrid restoration in primary teeth – An in vitro study
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Background: Glass ionomer restorations are widely employed in the field of pediatric dentistry. There is a constant demand for a durable restoration that remains functional until exfoliation. This study aimed to measure and compare the effect of a novel coating material (EQUIA Forte Coat) on the microleakage of glass hybrid restoration (EQUIA Forte HT) in primary teeth. Material and method: Thirty cavitated (class-II) primary molars were allocated randomly into two groups based on the coat application; uncoated (control) and coated group (experimental). Cavities were prepared by the use of a ceramic bur (CeraBur) and restored with EQUIA Forte HT with or without applying a protective coat (EQUIA Forte Coat). Samples went through the

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Publication Date
Wed Nov 05 2025
Journal Name
Journal Of Oral Biology And Craniofacial Research
The effect of thermocycling on fracture resistance of zirconia crowns cemented with polylysine modified resin cements (Comparative in vitro study)
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ABSTRACT Background: resin cement type and intraoral temperature fluctuations may affect the fracture performance of successful zirconia restorations. To fill this gap, the purpose of this study is to evaluate and compare the influence of thermocycling on fracture resistance and mode of failure of monolithic zirconia crowns luted with Rely X™ U200 and BreezeTMself-adhesive resin cements as well as imply the effect of adding 2 % of polylysine (PLS) to these cements. Materials: 64 maxillary premolars were milled out of zirconia blocks using CAD/CAM milling system. They were divided into four groups (n = 16) according to the cement type. Four different resin cements were used (RelyXTMU200, Breeze™, RelyX™ U200 with 2 % PLS

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Publication Date
Fri Oct 30 2020
Journal Name
Journal Of Economics And Administrative Sciences
Comparison between method penalized quasi- likelihood and Marginal quasi-likelihood in estimating parameters of the multilevel binary model
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Multilevel models are among the most important models widely used in the application and analysis of data that are characterized by the fact that observations take a hierarchical form, In our research we examined the multilevel logistic regression model (intercept random and slope random model) , here the importance of the research highlights that the usual regression models calculate the total variance of the model and its inability to read variance and variations between levels ,however in the case of multi-level regression models, the calculation of  the total variance is inaccurate and therefore these models calculate the variations for each level of the model, Where the research aims to estimate the parameters of this m

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Publication Date
Tue Jul 17 2018
Journal Name
Materials Research Express
Structural, electronic and thermodynamic properties of bulk and surfaces of terbium dioxide (TbO<sub>2</sub>)
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This contribution reports a comprehensive investigation into the structural, electronic and thermal properties of bulk and surface terbium dioxide (TbO2); a material that enjoys wide spectra of catalytic and optical applications. Our calculated lattice dimension of 5.36 Å agrees well with the corresponding experimental value at 5.22 Å. Density of states configuration of the bulk structure exhibits a semiconducting nature. Thermo-mechanical properties of bulk TbO2 were obtained based on the quasi-harmonic approximation formalism. Heat capacities, thermal expansions and bulk modulus of the bulk TbO2 were obtained under a wide range of temperatures and pressures. The dependency of these properties on operational pressure is very evident. Cle

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Publication Date
Sun Mar 01 2015
Journal Name
Current Research In Microbiology And Biotechnology
Evaluation for the Cytotoxic Effect of Exotoxin A Produced by Pseudomonas aeruginosa on Mice by using Cytogenetic Parameters
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This research was conduct to evaluate the cytotoxic effect of exotoxin A (ETA) produced by Pseudomonas aeruginosa on mice in comparison with (phosphate buffer saline (PBS) as a negative control. The effect of the toxin was measured by employing the cytogenetic analysis which included (the mitotic index (MI), chromosomal aberrations (CAs), micronucleus (MN) and sperm abnormalities) parameters. In order to specify the cytotoxic effect of the toxin, three doses of ETA (125, 250 and 500 ng/ml) were used. Results showed that ETA was found to cause a significant decrease in mitotic index (MI) percentage, while significant increase in micronucleus (MN), chromosomal aberrations (CAs) and sperm abnormalities parameters in compression with control wa

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Publication Date
Mon Apr 01 2024
Journal Name
Latin American Journal Of Pharmacy
The protective effect of iraqi Juniperus oxycedrus plant on acute kidney injury induced by lipopolysaccharide in mice model
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Inflammatory control is essential to diminish injury and make renal injury treatment simpler. Proposed therapeutics have primarily targeted pro-inflammatory variables. Juniperus oxycedrus was frequently used to treat a variety of infectious disorders, hyperglycemia, obesity, TB, bronchitis, inflammation, and pneumonia. Juniperus oxycedrus twigs and leaves were defatted with n-hexane using Soxhlet apparatus then the residue of plant material dried and re-extracted sequentially by two different solvents Ethylacetate and methanol. The pro-inflammatory markers IL-1 and iNOS, as well as the potential kidney biomarker KIM-1, TNF-α, and transcription factor NF-KB were measured using the RealTime Quantitative qPCR method. The results showed that J

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Publication Date
Tue Oct 01 2019
Journal Name
Biochemical And Cellular Archives
α-TOCOPHEROL FOLIAR APPLICATION CAN ALLEVIATE THE ADVERSE EFFECT OF SALINITY STRESS ON WHEAT PLANT, TRITICUM AESTIVUM L.
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Pots experiment was conducted at the greenhouse of botanical garden belong to Department of Biology, College of Education for Pure Science, Ibn-AL-Haithum, University of Baghdad, for growth season 2018-2019. The aim of the experiment was to study the effects of foliar application of a-tocopherol concentrations (0, 50, 100, 150, 200 mg.L-1) on growth parameters and the activity of some antioxidant enzymes of wheat plant irrigated with sodium chloride concentrations (0, 75, 150, 225) mM.L-1. Salinity reduced plant growth parameter, plant height, flag leaf area, flag leaf chlorophyll content and increased the activity of antioxidant enzymes, superoxide dismutase and peroxidase. Plant growth parameters were enhanced by foliar application of a-t

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Publication Date
Mon Jun 01 2020
Journal Name
Iraqi Journal Of Physics
Effect depositions parameters on the characteristics of Ni0.5Co0.5Fe2O4 nanocomposite films prepared by DC reactive magnetron Co-Sputtering technique
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In this work, spinel ferrites (NiCoFe2O4) were prepared as thin films by dc reactive dual-magnetron co-sputtering technique. Effects of some operation parameters, such as inter-electrode distance, and preparation conditions such as mixing ratio of argon and oxygen in the gas mixture, on the structural and spectroscopic characteristics of the prepared samples were studied. For samples prepared at inter-electrode distance of 5 cm, only one functional group of OH- was observed in the FTIR spectra as all bands belonging to the metal-oxygen vibration were observed. Similarly, the XRD results showed that decreasing the pressure of oxygen in the gas mixture lead to grow more crystal planes in the samples prepare

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